var readline = require('readline-sync')
readline.setDefaultOptions({prompt: ''})
var readline = readline.prompt
while(line = readline()){
  let [n,m] = line.split(' ').map(item => parseFloat(item))
  let i = 0
  let res = 0
  while(i < m){
    res += n
    n = Math.sqrt(n)
    i++
  }
  console.log(res.toFixed(2))
}